1. Field of the Invention
This invention relates to circuit switchgears (service plugs) that can open electric circuits to interrupt circuit current. More particularly, the invention is directed to a lever holding mechanism that can hold a lever in an erect position so that operability is improved, the folding type lever being foldable by pivoting.
2. Background
In switchboards for high-voltage circuits and the like, a circuit switchgear is constructed in the following manner lest an operator should receive an electric shock. When the cover of a switchboard has been opened, a plug disposed on the switchboard is pulled out of a terminal fixed to the switchboard main body so that the circuit current is interrupted.
Recently, electric cars attract attention as nonhazardous vehicles with no emission. Since such electric cars have high-voltage circuits for driving motors, it is also necessary to interrupt circuit current in servicing the cars for the same reason. To meet such needs, proposed for conventional electric cars is a circuit switchgear (connector device) that contains a high-voltage circuit inside a switchboard and that causes the high-voltage circuit to be automatically electrically opened when the cover of the switchboard has been opened.
FIG. 9 is a perspective view showing a conventional connector device, and FIG. 10 is a sectional view of a cover closing process of the conventional connector device. A female connector 3 is fixed inside a box-like housing 1 whose upper surface is opened. The female connector 3 is connectable to external high-voltage wires 5a, 5b through a connector terminal 6. A cover 7 for opening and closing the opening of the housing 1 is arranged on the housing 1. The cover 7 is pivotally movable about pivoting shafts 9. A guide 11 is disposed on the cover 7. The guide 11 holds a male connector 13 and a guide member 15 so that the male connector 13 and the guide member 15 are movable in a direction orthogonal to the pivoting shafts 9. Further, as shown in FIG. 10, a spring 17 is interposed between the internal wall of the guide 11 and the male connector 13. The spring 17 urges the male connector 13 and the guide member 15 toward the pivoting shafts 9.
In the connector device 19, when the cover 7 has been closed, the male connector 13 nears the female connector 3 while depicting an arcuate locus about the pivoting shafts 9. Therefore, in the process of engaging with the female connector 3, the male connector 13 moves away from the pivoting shafts 9 against the urging force of the spring 17 by the guide member 15 coming in contact with an internal wall 20a of a guide hole 20, and then the male connector 13 moves closer to the pivoting shafts 9 through the urging force of the spring 17 again. Accordingly, the male connector 13 engages with the female connector 3 while absorbing a displacement caused by the arcuate locus during the engaging process, so that conduction between the high-voltage wires 5a, 5b can be established.
On the other hand, when the cover 7 has been opened, the male connector 13 gets out of the female connector 3 while moving away from the pivoting shafts 9 again, so that the high-voltage circuit between the high-voltage wires 5a, 5b is electrically opened and the circuit current is hence automatically interrupted.
However, in the aforementioned conventional circuit switchgear, the male connector 13 is disposed on the cover 7 and the male connector 13 is engaged with and disengaged from the female connector 3 by opening and closing the cover 7 so that the high-voltage circuit can be automatically opened and closed. Therefore, there is a possibility that an operator will erroneously close the cover 7 during inspection. For this reason, it is preferable to be considered that the circuit switchgear be of such a structure that a plug main body or the like having short-circuit terminals integrally arranged thereon can be completely separated from a circuit accommodating body.
Further, in the aforementioned circuit switchgear, no handle such as a lever is arranged on the cover 7. Therefore, the cover opening and closing operation has been difficult. If a lever is arranged so as to simply project from the cover 7 to overcome the aforementioned problem, such lever becomes a hindrance in an electric car or the like in which only a limited component mounting space is available. Further, even if a folding type lever being folded by pivoting is arranged on the cover 7, the folding type lever imposes the problem of impaired operability with the lever pushing or pulling force not being applied in the same direction as the terminal engaging and disengaging direction due to the pivot of the folding type lever.